## Filling in Blanks: The General Case

Discussion about the puzzle behind the previous post led to this question: Is it possible to construct a similar question, where there are three of five values ...

## Filling in Blanks

Here’s an interesting mean/median question. Assume your lab assistant took five readings, but only recorded three of them: -3, 5, and 7. The assistant als...

## It’s Always Monday

In this post, I discuss the Sleeping Beauty problem, which explores how perception can affect assessment of probabilities. First, the video that introduced me t...

## Nested Isosceles Triangles

Today, I’m going to write up a quick geometric proof. Here’s the original puzzle that inspired it. Given that $$AC = AB$$ and that \(AE = DE = CD = ...

## Types of Numbers

Elementary school students spend most of their time working with counting numbers, that is, the non-negative integers. As students progress through secondary sc...

## Improper vs Mixed Fractions: A Six-Year-Old’s Perspective

I often discuss mathematics with my six-year-old son. As a teacher, my goal is to try to pinpoint where it is that student understandings go astray. As a parent...